Eoin Morgan admitted England paid the price for a "really bad day in the field" as they succumbed to defeat against Pakistan.

Morgan, England's captain, conceded his side "made mistakes we don't normally make" that "cost us probably 15-20 runs in the field." With Pakistan securing their first win in 12 ODIs by 14 runs, the consequences of such fumbles are obvious. As a result, he insisted England's attitude to that part of their game would have to improve.

"Fielding is an attitude thing," Morgan said. "So it's a matter of taking our stand-off attitude in the field today and getting back to our positive attitude where we go for everything. We need to create that fearless nature where we maybe take a half chance rather than standing off a normal chance."

If there was one moment that summed up England's performance in the field in Nottingham, it came in the 46th over.

Joe Root, at point, had just pulled off a fine save in the field to prevent a well-timed cut from Sarfaraz Ahmed. But then, with Sarfaraz just out of his ground, Root threw fiercely at the stumps only to see the ball bissect the fielders backing up and concede four over-throws. It was reflective of a somewhat messy showing that was in marked contrast to their excellence at The Oval.

The nadir of England's performance in the field came with Jason Roy's dropping of Mohammad Hafeez. It was, by any standards, a straightforward chance: a mis-hit drive spooned up to long-off; a chance that, at this level, would be expected to be held every time. But the chance went down - Roy seemed to suggest the sun had caused him some difficulty; it didn't seem obviously apparent that it should have done - and Hafeez, who was on 14 at the time, went on to top-score for Pakistan with 84.

All sides drop the odd catch, of course. But the real issue for England here was that it wasn't so much an aberration as reflective of England's general performance in the field. ESPNcricinfo's figures suggest there were 13 mis-fields in all.

In the first over of the innings, Morgan failed to stop a routine effort at point to concede an unnecessary boundary. Maybe he was slightly worried about his recently fractured finger - he insists it is fine - but it was an out-of-character error that seemed to set the tone for his side's efforts. It was a fielding performance that would have had Nasir Jamshed or Monty Panesar tutting at their TV screens in disgust.

Some will blame complacency. But even the sub fielder, James Vince, fumbled a simple ball on the boundary that conceded an extra run. It is hard to believe Vince, who has played only 10 ODIs and is fighting to gain a place in the side, could be complacent.

It seems more likely that concentration was the issue. A combination of nerves, a full house - many of them vocally supporting Pakistan - and the sense of expectation growing upon this England side, might have resulted in these fumbles. Either way, it will be a worry for an England side that prided itself on its performance at The Oval.

It wasn't a uniform story, though. Jos Buttler, one of the few men who endured a modest game in the field at The Oval, took a sharp stumping, while Chris Woakes held onto a World Cup record four outfield catches; one of them an outstanding effort on the long-on boundary. No non-keeper has ever taken more catches in an ODI for England. Jonny Bairstow, sweeping on the cover boundary, could also feel satisfied with his work, while Moeen Ali bowled especially well.

The rest? It was an oddly sloppy-looking performance that, according to ESPNcricinfo's figures, saw England concede 17 more runs than might be expected. Combined with the 11 wides their bowlers gave way, it left England chasing nearly 30 more than might have been the case. So while Morgan saw positive with his side's performance with bat and ball, he put the blame for this defeat squarely at the feet of the team's fielding performance.

"With the ball we restricted them, bearing in mind the wicket was good and the outfield fast," Morgan said. "And we recovered with the bat with that substantial partnership between Jos Buttler and Joe Root.

"Those guys played brilliantly but they did just keep us in the game. They needed more help either from the other four in the top six or the guys down the order.

"We've gone from one of our best performances in the field at The Oval to a, not extremely bad one, but one that has cost us probably 15-20 runs. And what were we: 14 runs short?"

England's problems might not be limited to the fielding, either. With Adil Rashid proving expensive (he went for 43 from five overs), Morgan only felt able to allow him five overs.

Partially as a result, their over-rate suffered to the extent that there were more than three overs remaining by the time England would have been expected to complete their overs. In all, Pakistan's innings over-ran by 19 minutes, though Morgan insisted the rate was cleared by the umpires.

"I think our over-rate was good," he said. "The umpires are my only gauge and they said we were level with three overs to go."

It's only a few games since Morgan served a one-match suspension for repeated over-rate violations. While there is an amnesty on such issues for global events like this, the possibility that Morgan could be censured again here is very real. While that may only amount to a fine, it will remain on his record and be taken into account should England over-run again. Coming at this stage of the tournament, it is also a real concern. England do not want to be without their captain for the latter stages of the competition.

For that to be relevant, though, they need to get there. And if they field like this, there is no guarantee at all of that.